its hard to give picture how to lay it out without standing there and looking from different vantage points from the house, yard, side, top, etc. I would incorporate lots of twists, turns and maybe a land bridge, just to be a little different.
I know what you mean with the hill, I am starting one saturday with a 6-7' elevation drop over 24' of stream. I can't wait, i'm getting ansy just thinking about it.
Efficiency = Profit